Solid sheet metal springs for cooling actuators have been used in injection molding systems such as disclosed in U.S. Pat. Nos. 8,349,244 and 8,562,336. These prior cooling devices comprise a solid body of sheet metal of relatively high mass in excess of 5 grams that is adapted to exert a spring force by forced deformation of a portion of the solid sheet of metal. This same sheet of metal is purposely disposed in direct heat conductive contact with a relatively large surface of the hot metal housing of an actuator typically in excess of 10 square millimeters that itself is disposed in heat conductive communication with a fluid distribution manifold that is heated to an elevated temperature sufficient to melt polymer materials. Over time, the ability of the sheet metal spring body to readily deform and provide an effective spring force is degraded by the very high level of heat to which the sheet metal body is subjected, the sheet metal spring body also acting to conduct heat from the actuator housing body to a cool clamp plate.